JPH0214761A - Method and device for cleaning grit and scum of grit chamber - Google Patents

Abstract

PURPOSE:To carry out the sure sepn. and easy post treatment of scum and grit by agitating and cleaning the grit and scum, selecting out heavy matter, crushing the middle layer suspensions, separating the same to the cleaned grit and the cleaned scum, joining the cleaned grit with the heavy matter, and dehydrating the leaned scum, then discharging the same. CONSTITUTION:The stained grit recovered from a grit chamber 10 by a grit removing machine 1 and the screen scum recovered to a screen dust remover 2 are charged into a separating and agitating tank 7 filled with cleaning water where the grit and the scum are agitated and washed. The heavy matter is screened out by gravity settling and the middle layer suspensions are drawn out together with the cleaning water and are crushed by a crushing pump 11 having a crushing function; thereafter the suspensions are classified 12 and are separated to the cleaned grit and the cleaned scum according to the various values of sp. gr. Further, the cleaned grit is joined with the heavy matter screened out of the separating and agitating tank 7 and is ejected by an ejecting machine 13 after dewatering or the cleaned scum is dehydrated by a dehydrator 15 and is discharged as general waste to the outside of the plant or to the ensuing treatment in the plant. As result, the scum and the grit are surely separated and the post treatment is facilitated.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for cleaning sieve sludge, sludge, sludge, etc. generated from settling basins in relay treatment plants, final treatment plants, etc. in sewerage systems, and Regarding equipment.

(Conventional technology) Exhaust materials such as slag, sludge, and sludge that are separated and discharged from the settling basins of relay pumping stations and final treatment plants in sewers contain a large amount of putrefying organic matter, so it is difficult to transport and dispose of them. Sometimes it becomes a big problem in terms of environmental health.

Under these circumstances, various methods are being used to make the waste hygienic and easy to handle, mainly cleaning treatments, but there are many deficiencies in treatment effectiveness and rationality of the treatment system. The cleaning treatment method also has the following problems.

■ Insufficient removal and dissolution of soluble solids (excrement, etc.).

■ Separation of cleaning sand, cleaning sand, and sludge is insufficient.

■ Trouble caused by bulky garbage.

■ Trouble caused by hard dust such as metal.

■ Increasing the size of equipment and fluctuations in treatment effects due to fluctuations in the input tank and amount of sludge, and recent trends suggest that waste from relay pumping stations should normally be sent to a final treatment plant along with sewage for centralized treatment. More and more people are saying that it is desirable. However, in the current facility, the pipes are blocked due to sedimentation and accumulation of coarse dust, gravel, and sand.
In addition, damage to the pump due to metal gravel, etc., has become a problem, and is an obstacle to its realization.

Therefore, there has been a long-awaited development of a treatment method and device that can be used as pretreatment equipment for pumping at the relay pump station in future centralized treatment at final treatment plants and that can solve the problems (1) to (3) above. Ta.

(Problems to be Solved by the Invention) Conventional methods for cleaning dirty sand and shingles are generally known, for example, pressure water agitation type, air agitation type, mechanical agitation type, or drum type. This method also stirs and cleans the dirt or sand that has been introduced at the same time as the washing water is injected. Therefore, because cleaning is performed only by the stirring flow, it is difficult to dissolve soluble solids such as human excrement and to separate them from the membrane cleaning sheath. Insufficient cleaning of the surface-floating grass becomes insufficient, and in addition to problems such as emission of odor and generation of noise, there is also the problem of consuming a large amount of cleaning water.

The present invention has been made in view of the problems of the conventional technology in the cleaning treatment of sand and sediment generated in the relay pumping station in the sewer system and the settling basin of the final treatment plant. The purpose is to provide a method and device for cleaning sand and sediment that solves various problems and can be used as a pretreatment for pumping sand, etc. from a relay pump station to a final treatment plant, which is a trend in the future. be.

(Means for Solving the Problems) In order to achieve the above object, in the method of cleaning sand and sand in a sand settling basin according to the present invention, dirty sand recovered from the settling basin by a sand remover and a screen dust remover are used. The screen residue (shisa) collected in the process is put into a separation stirring tank filled with washing water, where it is agitated and washed, heavy objects are sorted out by gravity settling, and the middle-layer suspended objects are pulled out along with the washing water to activate the crushing function. After crushing with the equipped crushing pump, it is passed through a classifier and separated into washed sand and washed residue based on their light and heavy specific gravity.The washed sand is combined with the heavy material sorted and discharged from the separation stirring tank, and after draining, it is sent to the unloading machine. The washing residue is dehydrated through a dehydrator and then discharged as general waste to the next stage of treatment outside or inside the site, respectively.

In addition, the equipment includes a sludge quantitative feeder that stores the sludge collected by the sand remover from the sand settling basin and sends it out in fixed quantities, and a sludge feeder that collects the sewage from the settling basin through a screen and stores the collected screen residue (shisa), which is then pumped out in fixed quantities. A separate stirring tank equipped with an agitator so that the waste sand and sand sent out from both quantitative feeders are received into a tank filled with washing water and stirred and washed, and this separated stirring tank. A washing sand collector removes the heavy materials that have settled by gravity to the bottom of the tank while draining them, a crushing pump has a crushing function that pulls out the suspended solids in the middle layer of the separation stirring tank along with the cleaning water, and sends them out while crushing them. It consists of a classifier that uses centrifugal force to separate the crushed material into washed sand, which has a heavy specific gravity, and washed residue, which has a light specific gravity.

Furthermore, the waste sand and shingles put into the separation agitation tank are passed through a coarse shiz collecting screen in the tank to recover coarse shingles, and after the collected coarse shingles are crushed by a crusher, they are passed through a sheath quantitative feeder or separated and stirred. There is a way to refill the tank.

Alternatively, there is a method in which the cleaning residue separated by the classifier is received in a shingle recovery tank together with the cleaning water, and a part of the cleaning water is returned to the separation stirring tank.

Further, it is preferable that the excess washing water in the shingle recovery tank and the dewatering liquid discharged from the dehydrator are returned to the settling basin downstream of the screen dust remover.

(Function) Sewage introduced into the settling basin 10 flows gently in the direction of arrow A in FIG. 1, and sludge, sludge, etc. that have settled due to gravity are deposited at the bottom of the settling basin.

A sand remover 1 is installed on the upstream side of this settling basin 1G, and a screen dust remover v! is installed on the downstream side. 12 will be provided.

Sand removal I! ! 1 scoops up the dirt from the bottom of the sand settling basin and stores it in the metering pump 5a of the sand chamber l feeder 5.

Since all of the wastewater heading downstream passes through the screen dust remover I2, bulky waste mixed in the wastewater is caught by the screen 2a. These are scraped up as screen residue (shisa) and sent to the constant liter hopper 6a of the screener quantitative supply tl16.
stored in.

The dirt and sand stored in both hoppers 5a and 6a are sent out in fixed amounts from the bottoms of the respective hoppers by feeding devices 5b and 6b, and thrown into a separation stirring tank 7. In the separation stirring tank 7, the tank is filled with cleaning water and stirred by the stirrer 3, so that dirt is loosened and simple cleaning is performed.

Bulky waste such as driftwood and old tires is collected by a large shingle collection screen 4, crushed by a crusher 9, and then thrown into the separation stirring tank 7 again. The materials that have passed through the coarse shredder collection screen 4 are stirred and cleaned again by the agitator 3a, and heavy materials such as metals and stones settle by gravity and are deposited at the bottom of the tank as washed sand. It is carried out of the tank at 13.

On the other hand, the debris floating in the agitation flow is pulled out from the middle layer along with the washing water by a pump 11 with a crushing function, and is crushed into small pieces while being pumped to a classifier 12. The garbage and sewage pumped into the classifier 12 are separated there by cyclone or centrifugal action into washed sand with a heavy specific gravity and washed residue with a light specific gravity, and the washed sand is taken out from the bottom of the classifier and subjected to the previous separation. After combining with the washed sand taken out from the stirring tank 7, it is drained by the washed sand recovery machine 13 and discharged to the outside of the system. In addition, the washing residue taken out from the upper part of the classifier 12 is introduced into the shisa recovery tank 14 filled with washing water, where it is roughly washed, passed through a dehydrator 15, and then discharged as general waste to the next process outside or inside the plant. be done.

A part of the washing water in the shingle recovery tank 14 is returned to the separation stirring tank 7. The overflow is taken out together with the water removed from the dehydrator 15 and injected into the downstream part of the screen of the settling basin 10.

(Example) Preferred embodiments of the invention will be described with reference to the drawings.

The sludge feeder 5 and the slag quantitative feeder 6 have hoppers 5a and 6a to collect the sludge or sludge collected by the sand remover or screen dust remover 2, store each separately, and send out a fixed amount of each. A feeding device 115b, 6b consisting of a flat conveyor, screw conveyor, etc. is provided at each bottom.

The sand remover 1 removes dirt, sludge, etc. that have settled and accumulated at the bottom of the settling basin by scooping up or the like, and a packet type sand remover, a pump suction type sand remover, or the like is used.

The packet-type sand remover shown in the figure includes an endless chain 1a driven by a motor, and a plurality of packets 1b attached to the endless chain at predetermined intervals. Each packet is moved parallel to the pond bottom by driving the chain 1a. It is used to scoop up dirty sand. 1C is a guide roller that guides the chino 1a.

The screen dust remover 2 is installed in the sand settling basin 10 so as to be located downstream of the sand remover 1, and scrapes up a screen 2a such as a bar screen and shingles piped into the screen along this screen. It consists of a rake-equipped chino 2b with a rake attached to an endless chino.

The separation agitation tank 7 agitates the filthy sand and shiso fed by each quantitative feeder 5.6 underwater, loosens the mud, and washes it while removing bulky waste and heavy solids such as metal, glass, and pebbles. It is separated into turbid water mixed with shisa and sediment, and is separated into tank 7a.
A stirrer 3.3a is provided on the side wall.

The bulky shingle collection Ia4 is comprised of an inclined conveyor that scoops up bulky garbage such as driftwood and old tires while draining it from the water.

The crushing pump 11 is a pump with a crushing function, and pulls the fine floating garbage that has passed through the coarse shredder collection Akebono 4 out of the tank from the middle layer so as to suck it together with the polluted water, and crushes it into smaller pieces before sending it to the subsequent classifier 12. It is pumped.

The classifier 12 uses centrifugal force or the action of a cyclone to classify the mixed polluted water and crushed shingles pumped from the crushing pump 11 into shingles and sandy water. is drained while being washed by the washing sand recovery Vs13 and discharged to the outside of the system.

The washed sand recovery machine 13 washes and drains and discharges the sand that has been classified and washed in the classifier 12 and settled, and the heavy solids that have been separated and settled in the separation stirring tank 7. It is held in an inclined manner.

The cleaning tank 14 receives the turbid water mixed with crushed shreds that has been classified by the classifier 12, and the washed shisha separates and discharges solids having a particle size larger than a set size using a collection screen 20 consisting of a fine automatic screen and sends it to the dehydrator 15. Feed, screen flow sewage,
The water is circulated to the separation stirring tank 7, and excess water is returned to the settling basin 10 by overflow.

The dewatering machine 15 dehydrates the crushed and cleaned shingles that have been separated and collected in the washed shingles collection tank 14. The dehydrated shingles are transported outside the plant at carryout@21 for processing, or are processed at the next stage within the plant. (e.g. incinerated). The dehydrated filtrate is returned to the settling basin 10.

Coarse shreds are collected in the separation stirring tank 7! The bulky waste separated and collected by II4 is sent to the crusher +19 by the bulky shear transfer conveyor 8, where it is crushed into a size that does not affect the subsequent processing, and is either re-injected into the separation stirring tank 7 as it is, or sent to the crusher +19 by the conveyor 8. 22, it is once received into the hopper 6a of the shisa quantitative feeder 6, and then re-injected into the separation stirring tank 7 through this quantitative feeder.

The washed sand carried out from the washed sand collecting machine 13 is transferred to the carrying out machine 1.
After receiving the waste into a storage facility 17 consisting of a hopper and the like, the waste is discharged outside the site or to the next stage of treatment as general waste.

(Effects of the Invention) Since the present invention is configured as described above, it has the following effects.

■Water consumption can be reduced because cleaning water is recycled.

■ Underwater crushing is highly effective in treating soluble solids such as human waste.

■ Sorting and crushing makes the shingles uniform and improves dewatering performance. Furthermore, the coarse shreds that have been washed are easier to crush, and furthermore, by sorting, the size of the underwater crusher can be reduced.

■ Significant decrease in solubility of shisa.

■ Separation of sand and sediment is ensured, making post-processing easier.

■ Underwater crushing reduces the diameter of the shingles, increasing the area of contact with the cleaning water and increasing the cleaning effect.

■ Good separation of sludge.

■ Both the dirty sand and shisa are washed in multiple stages, resulting in an extremely high degree of cleaning.

- In addition to washed sand and shredders, heavy solids such as metals and pebbles can be easily and reliably separated and recovered.

■ It can be used as a pretreatment for future trends, such as pumping shisa.

■By adding a fixed amount of shingles and waste sand, peak cutting and dry running can be prevented, making the processing equipment economical and compact.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a system diagram showing an apparatus for carrying out the method for cleaning sand and sand in a sand settling basin according to the present invention, and FIG. FIG. 1 is a flow sheet diagram conceptually showing a method and an apparatus. 1...Sand remover 3.38...Agitator 5...Dirty sand quantitative feeder 7...Separation stirring tank 10...Sand settling tank 12...Classifier 2...Screen dust remover 4... Coarse shag collecting machine 6... Shim quantitative feeding machine 9... Crushing machine 11... Crushing pump 13... Washed sand recovery machine 14... Washed shingles collection tank 15... Dewatering machine

Claims (5)

[Claims] (1) Dirty sand collected from the sand settling basin with a sand remover and screen residue collected with a screen dust remover are charged into a separation stirring tank filled with washing water, stirred and washed, and heavy The suspended solids in the middle layer are extracted by gravity sedimentation, and suspended matter in the middle layer is pulled out along with the washing water, and then crushed using a crushing pump equipped with a crushing function.
The washed sand is separated into washed sand and washed residue based on their light and heavy specific gravity, and the washed sand is combined with the heavy materials sorted and discharged from the separation stirring tank, and after being drained, it is sent to a carry-out machine, and the washed residue is passed through a dehydrator to be dehydrated. 1. A method for cleaning and treating sediment and shingles in a settling pond, which is characterized in that they are discharged as general waste to the next stage of treatment outside or inside the site, respectively. (2) A sludge quantitative feeder that stores the sludge collected by the sand removal machine from the settling basin and sends it out in fixed quantities, and a sludge feeder that stores and sends out the screen residue (shisa) collected by screening the sewage from the settling tank. A shisa quantitative feeder, a separation agitation tank equipped with an agitator to receive the dirty sand and shisa sent out from both of these quantitative feeders into a tank filled with washing water and agitate and wash it, and the bottom of this separation agitation tank. A washed sand recovery machine that carries out heavy materials that have settled due to gravity while draining them, a crushing pump that has a crushing function that pulls out the floating solids in the middle layer of the separation stirring tank along with the cleaning water, and sends them out while crushing them, and crushed materials crushed by the crushing pump. A cleaning treatment device for sand settling and shisa in a settling basin, characterized by comprising a classifier that separates washed sand with a heavy specific gravity and washed residue with a light specific gravity by centrifugal force. (3) Dirty sand and shingles put into the separation stirring tank are passed through a coarse shingle collection screen in the tank to recover coarse shingles, and after the collected coarse shingles are crushed by a crusher, they are passed through a shredded quantitative feeder or separated. 2. The method for cleaning sand and sand in a sand settling basin according to claim 1, wherein the sand is re-injected into the stirring tank. (4) The settling basin according to any one of claims 1 and 2, wherein the washing residue separated by the classifier is received in the sand collection tank together with the washing water, and a part of the washing water is returned to the separation stirring tank. A method for cleaning sand and sand. (5) Sand settling in the settling basin according to claims 1, 3, and 4, wherein surplus washing water in the shisa recovery tank and dewatering liquid discharged from the dehydrating machine are returned to the settling basin downstream of the screen dust remover; How to clean shisa.